Whitney Cranshaw is an entomologist and professor of plant sciences at Colorado State University in Fort Collins. There are more than 80 species of ladybugs in Colorado, Cranshaw said, but the convergent ladybeetle is the only one that heads for the hills.

“The explanations are still tentative,” Cranshaw said. “It allows them to mix. They do a lot of mating. It is awfully protected in the high country.”